feat: support dependencies from pyproject.toml

rsconnect/main.py

@@ -1106,7 +1106,7 @@ def _warn_on_ignored_requirements(directory: str, requirements_file_name: str):
     default="requirements.txt",
     help=(
         "Path to requirements file listing the project dependencies. "
-        "Any file compatible with requirements.txt format or uv.lock is accepted, "
+        "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
         "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
         "Must be inside the project directory."
     ),
@@ -1287,7 +1287,7 @@ def deploy_notebook(
     default="requirements.txt",
     help=(
         "Path to requirements file listing the project dependencies. "
-        "Any file compatible with requirements.txt format or uv.lock is accepted, "
+        "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
         "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
         "Must be inside the project directory."
     ),
@@ -1544,7 +1544,7 @@ def deploy_manifest(
     default="requirements.txt",
     help=(
         "Path to requirements file listing the project dependencies. "
-        "Any file compatible with requirements.txt format or uv.lock is accepted, "
+        "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
         "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
         "Must be inside the project directory."
     ),
@@ -1974,7 +1974,7 @@ def generate_deploy_python(app_mode: AppMode, alias: str, min_version: str, desc
         type=click.Path(dir_okay=False),
         help=(
             "Path to requirements file listing the project dependencies. "
-            "Any file compatible with requirements.txt format or uv.lock is accepted, "
+            "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
             "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
             "Must be inside the project directory."
         ),
@@ -2341,7 +2341,7 @@ def write_manifest():
     type=click.Path(dir_okay=False),
     help=(
         "Path to requirements file listing the project dependencies. "
-        "Any file compatible with requirements.txt format or uv.lock is accepted, "
+        "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
         "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
         "Must be inside the project directory."
     ),
@@ -2460,7 +2460,7 @@ def write_manifest_notebook(
     type=click.Path(exists=True, dir_okay=False),
     help=(
         "Path to requirements file listing the project dependencies. "
-        "Any file compatible with requirements.txt format or uv.lock is accepted, "
+        "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
         "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
         "Must be inside the project directory."
     ),
@@ -2615,7 +2615,7 @@ def write_manifest_voila(
     type=click.Path(dir_okay=False),
     help=(
         "Path to requirements file listing the project dependencies. "
-        "Any file compatible with requirements.txt format or uv.lock is accepted, "
+        "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
         "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
         "Must be inside the project directory."
     ),
@@ -2832,7 +2832,7 @@ def generate_write_manifest_python(app_mode: AppMode, alias: str, desc: Optional
         type=click.Path(dir_okay=False),
         help=(
             "Path to requirements file listing the project dependencies. "
-            "Any file compatible with requirements.txt format or uv.lock is accepted, "
+            "Any file compatible with requirements.txt format, uv.lock, or pyproject.toml is accepted, "
             "a requirements.txt.lock retrieved with 'rsconnect content get-lockfile' is also supported. "
             "Must be inside the project directory."
         ),

rsconnect/subprocesses/inspect_environment.py

@@ -20,6 +20,12 @@
 from dataclasses import asdict, dataclass, replace
 from typing import Callable, Optional
 
+try:
+    import tomllib
+except ImportError:
+    # Python <3.11 doesn't have tomllib in the standard library
+    import toml as tomllib  # type: ignore[no-redef]
+
 version_re = re.compile(r"\d+\.\d+(\.\d+)?")
 exec_dir = os.path.dirname(sys.executable)
 
@@ -78,6 +84,8 @@ def detect_environment(dirname: str, requirements_file: Optional[str] = "require
         result = pip_freeze()
     elif os.path.basename(requirements_file) == "uv.lock":
         result = uv_export(dirname, requirements_file)
+    elif os.path.basename(requirements_file) == "pyproject.toml":
+        result = pyproject_dependencies(dirname, requirements_file)
     else:
         result = output_file(dirname, requirements_file, "pip")
         if result is None:
@@ -255,6 +263,47 @@ def uv_export(dirname: str, lock_filename: str):
     }
 
 
+def pyproject_dependencies(dirname: str, pyproject_filename: str):
+    """Read project.dependencies from a pyproject.toml file as a requirements spec.
+
+    Emits a requirements.txt file listing the top-level dependencies declared
+    in ``[project].dependencies``. Unlike ``uv.lock``, the result is not a
+    fully resolved lock and Connect will perform dependency resolution at
+    deploy time.
+    """
+    pyproject_path = pyproject_filename
+    if not os.path.isabs(pyproject_filename):
+        pyproject_path = os.path.join(dirname, pyproject_filename)
+
+    if not os.path.exists(pyproject_path):
+        raise EnvironmentException(f"pyproject.toml not found: {pyproject_filename}")
+
+    try:
+        with open(pyproject_path, "r", encoding="utf-8") as f:
+            pyproject = tomllib.loads(f.read())
+    except Exception as exception:
+        raise EnvironmentException(f"Error reading {pyproject_filename}: {exception}")
+
+    project = pyproject.get("project", {})
+    dependencies: list[object] = project.get("dependencies", [])
+    if not isinstance(dependencies, list):
+        raise EnvironmentException(f"Invalid project.dependencies in {pyproject_filename}: expected a list of strings.")
+
+    requirements = filter_pip_freeze_output("\n".join(str(dep) for dep in dependencies))
+    requirements = (
+        f"# requirements.txt generated from pyproject.toml by rsconnect-python on "
+        f"{datetime.datetime.now(datetime.timezone.utc)}\n"
+        f"{requirements}"
+    )
+
+    return {
+        "filename": "requirements.txt",
+        "contents": requirements,
+        "source": "pyproject_toml",
+        "package_manager": "pip",
+    }
+
+
 def filter_pip_freeze_output(pip_stdout: str):
     # Filter out dependency on `rsconnect` and ignore output lines from pip which start with `[notice]`
     return "\n".join(

tests/test_environment.py

@@ -194,6 +194,54 @@ def test_uv_lock_export(tmp_path):
     assert env.package_manager == "uv"
 
 
+def test_pyproject_dependencies(tmp_path):
+    project_dir = tmp_path / "project"
+    project_dir.mkdir()
+    (project_dir / "pyproject.toml").write_text(
+        "[project]\n"
+        "name = 'demo'\n"
+        "version = '0.0.0'\n"
+        "dependencies = [\n"
+        "    'aiofiles==24.1.0',\n"
+        "    'annotated-types>=0.7.0',\n"
+        "    'rsconnect-python==1.0.0',\n"
+        "]\n",
+        encoding="utf-8",
+    )
+
+    env = detect_environment(str(project_dir), requirements_file="pyproject.toml")
+
+    assert env.filename == "requirements.txt"
+    assert "aiofiles==24.1.0" in env.contents
+    assert "annotated-types>=0.7.0" in env.contents
+    # rsconnect dependency lines must be stripped, matching the behavior of output_file() and pip_freeze()
+    dep_lines = [line for line in env.contents.splitlines() if line and not line.startswith("#")]
+    assert not any("rsconnect" in line for line in dep_lines)
+    assert env.source == "pyproject_toml"
+    assert env.package_manager == "pip"
+
+
+def test_pyproject_dependencies_missing(tmp_path):
+    project_dir = tmp_path / "project"
+    project_dir.mkdir()
+
+    with pytest.raises(EnvironmentException, match="pyproject.toml not found"):
+        detect_environment(str(project_dir), requirements_file="pyproject.toml")
+
+
+def test_pyproject_dependencies_no_project_table(tmp_path):
+    project_dir = tmp_path / "project"
+    project_dir.mkdir()
+    (project_dir / "pyproject.toml").write_text("[build-system]\nrequires = ['setuptools']\n", encoding="utf-8")
+
+    env = detect_environment(str(project_dir), requirements_file="pyproject.toml")
+
+    assert env.filename == "requirements.txt"
+    assert env.source == "pyproject_toml"
+    # Header comment is present but no dependencies are listed.
+    assert all(line.startswith("#") or line == "" for line in env.contents.splitlines())
+
+
 class WhichPythonTestCase(TestCase):
     def test_default(self):
         self.assertEqual(which_python(), sys.executable)